The Cardiovascular System Flashcards
What are the 4 heart valves?
Tricuspid (right) Mitral (Left) - atrioventricular valves
Pulmonary, aortic - semi lunar valves
The right side of the heart pumps…to..
Deoxygenated blood to the pulmonary circulation
The left side of the heart pumps..to..
Oxygenated blood to the systemic circulation
The endocardium:
lines atria, ventricles, forms valves
Myocardium:
is the cardiac muscle
Epicardium:
covers external surface of the heart, also known as the pericardium
Identify the principle features of cardiac muscle (pericardium)
Central nucleus (usually one but sometimes 2), Intercalated discs, Branched fibres, blood vessels
What is the bundle of his?
the atrioventricular bundle (tricuspid and mitral valve)
What are purkinje fibres?
network of cardiac conducting fibres
What is atrial diastole?
blood gathers in atria and passes into the ventricles
What is atrial systole?
blood forced into the ventricles by atrial contraction
What is ventricular diastole?
ventricles fill with blood slowly
What is ventricular systole?
ventricles eject blood into the aorta and pulmonary trunk
What is the filling phase? how long?
0.5 sec. The atria in systole for the last third of this, ventricles in diastole. The AV valves open, and there is a rapid filling of the ventricles.
What is the Isovolumetric contraction?
0.05 sec. The AV valves close (first heart sound, ‘lub’) Semi lunar valves still shut, atria in diastole.
What is the ejection phase?
0.3 sec. The ventricular pressure now > arterial pressure. The semi lunar valves open, blood is rapidly ejected. Semi lunar valves snap shut (second hear sound, ‘dub’)
What is Isovolumetric relaxation?
0.08 sec. The ventricles are in diastole , AV valves open, cycle repeats itself.
What is tachycardia?
Heart rate in excess of normal
What is bradycardia?
Heart rate below normal.
Deoxygenated blood comes from the body to …..
Goes to the lungs from ….
From the body to the cranial and caudal vena cava…From the lungs to the pulmonary vein
Oxygenated blood comes from the lungs to ….oxygenated blood to the body comes from the…
From the lungs to pulmonary artery…To the body from the aorta
